static void editRecipientHtml(CommandSender sender, String emailString, RecipientAction action) {
   HtmlEmail email = htmlEmail.get(sender.getName());
   switch (action) {
     case ADD:
       try {
         email.addTo(emailString);
       } catch (EmailException e) {
         sendErrorMessage(sender, e);
         return;
       }
       LogHelper.showInfo("emailRecipientAdd", sender);
       return;
     case ADD_BCC:
       try {
         email.addBcc(emailString);
       } catch (EmailException e) {
         sendErrorMessage(sender, e);
         return;
       }
       LogHelper.showInfo("emailRecipientAdd", sender);
       return;
     case ADD_CC:
       try {
         email.addCc(emailString);
       } catch (EmailException e) {
         sendErrorMessage(sender, e);
         return;
       }
       LogHelper.showInfo("emailRecipientAdd", sender);
       return;
     case DELETE:
       try {
         email = removeRecipient(email, emailString);
       } catch (EmailException e) {
         sendErrorMessage(sender, e);
         return;
       }
       LogHelper.showInfo("emailRecipientDeleted", sender);
       return;
     case LIST:
       sender.sendMessage(composeReadableRecipientList(email));
     default:
   }
   htmlEmail.put(sender.getName(), email);
 }